Neutral dangling bond depletion in amorphous SiN films induced by magnetic rare-earth elements

Amorphous silicon–nitrogen (a-SiN) thin films doped with rare-earth elements (RE=Y, La, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Yb, and Lu) were prepared by cosputtering and studied by means of electron spin resonance. It was found that the neutral dangling bond density, [D0], of the a-SiN films decreases with the presence of magnetic REs and the drop in [D0] approximately scales with the de Gennes and/or the spin factor of each RE element. Similar to the decrease in Tc in RE-doped superconductors, our experimental results strongly suggest that an exchange-like interaction, H∼JRE-D0SRE·SD0, between the spin of the magnetic REs and that of the D0 is taking place.